Many electronic devices are designed to emit or respond to radiation. Examples of electronic devices include Organic Light Emitting Diodes (OLEDs). OLEDs are promising for display applications due to their high power conversion efficiency and low processing costs. OLEDs include organic active layers that can emit or respond to the radiation.
A waveguide (also called a “light pipe”) may be formed within an electronic device at an interface between layers having dissimilar refractive indices. The waveguide effect can occur when radiation propagating within a layer having a higher refractive index is reflected at an interface with another layer having a lower refractive index. The waveguide effect can cause radiation to propagate laterally as opposed to propagating towards the user of the electronic device. In electronic devices, the lateral propagation of radiation can reduce the efficiency of the electronic device (require more power for a desired level of intensity), increase optical cross talk between pixels, or a combination thereof. Conventional wisdom within the art is to reduce or eliminate the waveguide effect as much as possible.